Expressions, Variables and Assignments - A Concise and Practical Introduction to Programming Algorithms in Java - page 6

50cm in width, 100cm in height and 20cm in depth. We simply do compute
the volume in cubic meters m 3 by converting the dimension units into meter
equivalents and performing the product of these dimensions to get the volume.
Thus the volume of that 3D box is

0 . 2 m =0 . 1 m 3 . 0 . 5 m × 1 m ×

How do we program this? We simply need to evaluate the arithmetic expression
0 . 5 × 1 × 0 . 2

Program 1.3 Expression: Evaluating the volume of a 3D box
class VolumeBox

{
public static void main ( String [ ] args )

System . out . println (0.5

∗ 1 ∗ 0.2) ;

}
}

Storing the above program into filename VolumeBox.java , compiling and
executing it, we get the expected output:

0.1

Thus we can calculate the value of any arithmetic expression, say the generic
myExpression expression, and display its value by executing the instruction
System.out.println(myExpression); Of course, this straight number alone is not
very informative, so it is better to display a message on the console telling
what the number really means. We do this by printing the message without
the return carriage (line return) using the instruction System.out.print .

class VerboseVolumeBox {
public static void main ( String [ ] args )
System . out . print ( "Volume of the box (in cubic meters):" );
System . out . println (0.5 ∗ 1 ∗ 0.2) ;
}
}

Compiling and running this program yields the better verbose output:
Volume of the box (in cubic meters):0.1

1.3.1 Arithmetic operations and priority order

The arithmetic operations used in expressions are:

- The addition ( + )